Development of the Corpus Callosum: An MRI Study

Abstract

The size and shape of the corpus callosum and its major components (genu, body, and splenium) were measured by magnetic resonance imaging (MRI) in 118 normocephalic individuals aged from 1 postnatal week to 18.7 years. Genu, body, splenial, and total corpus callosal areas increased by 40-100% during the first year of life (p < 0.05). The genu expanded to a greater extent than the splenium during the first 6 years, while the splenium expanded to a greater extent between 7 and 18 years. The age-related difference in the maximal expansion of these structures indicated an anterior to posterior wave of corpus callosal enlargement during maturation, probably the consequence of differential axonal myelination. No sex differences existed during these two developmental phases for the genu, splenial, or total corpus callosal areas with or without scaling to the cerebral hemispheric volume. During infancy (0-24 months), however, the mean female splenial ratio (length/height) of 0.79 was greater than the male ratio of 0.65 (p = 0.024). The cerebral hemispheric length/height ratio was also greater in females, indicating that during infancy the female brain (and its component the corpus callosal splenium) is relatively longer than the male brain. This sex difference was confined to the splenium and disappeared with increasing age.

High angular resolution diffusion MRI reveals conserved and deviant programs in the paths that guide human cortical circuitry

“…After controlling for variation in overall developmental schedules across species, the corpus callosum continues to grow for an extended period of time in humans. We find that the corpus callosum ceases to grow somewhere between 1 to 2 years of age, which is consistent with the work of others who have shown that the corpus callosum ceases to grow several months to a few years after birth in humans (Giedd et al, 1999;Tanaka-Arakawa et al, 2015;Vannucci et al, 2017;Sakai et al, 2017). In mice, the corpus callsoum area only grows for a few days, which is also consistent with previous work (Wahlsten, 1984; but see Chuang et al, 2011).…”

Defining the Normal Dorsal Contour of the Corpus Callosum with Time

“…Multiple studies have demonstrated that there is not a consistent statistical change in the absolute callosal area between men and women throughout the life span. 15,16,[20][21][22][23] Our study also supports the dynamic evolution of the CC with time. Our data suggest that as patients age, the prevalence and depth of an anterior notch in the dorsal callosal surface increase significantly.…”

“…2 There is an initial growth of the genu beginning at birth to 5-6 years, followed by subsequent growth of the splenium until 10 -12 years. 19,20 Although debated in the literature, these changes do not seem to be sex-dependent. Multiple studies have demonstrated that there is not a consistent statistical change in the absolute callosal area between men and women throughout the life span.…”

Commentary: Mycoplasma pneumoniae-associated mild encephalitis/encephalopathy with a reversible splenial lesion: Report of two pediatric cases and a comprehensive literature review

“…The age effect on maturation is stronger in SCC than in other callosal subregions 16 . No sex difference is found in maturation during the development except infancy (0-24 months), in whom the SCC size is greater in females 15 . Maturation of CC is correlated with age 17 , and age at which the CC is immature corresponds to the prevalent age of MERS children.…”

“…SCC matures between 4 and 18 years of age 15,16 . The age effect on maturation is stronger in SCC than in other callosal subregions 16 .…”